Field of Invention
The present invention relates to overpack salvage drums and related methods. More particularly, the present invention relates to overpack salvage drums and related methods that exhibit improved sealing, stacking and manufacturing characteristics.
Description of Related Art
The U.S. Department of Transportation (“USDOT”) and the United Nations (“UN”) have established regulations for removable head salvage drums (see, e.g., 49 C.F.R. §173.3(c)), which are also known in the art and hereinafter referred to as overpack salvage drums. Overpack salvage drums are used in a variety of applications, including for the containment of packages that have been damaged, have otherwise become defective or have been found to be leaking, and/or for the containment of potentially hazardous solid materials while they are being transported. Shaw et al., U.S. Pat. No. 4,708,258, discloses a rotationally molded polyethylene overpack salvage drum that meets such USDOT and UN standards.
The overpack salvage drum according to Shaw et al. includes a single-walled drum body having an open end and a double-walled lid that is adapted to threadingly engage the open end of the drum body and thereby seal and contain a steel drum therein. A closed-cell foam gasket in the lid seals the closure between the lid and the drum body. The present invention improves upon the basic design of the overpack salvage drum disclosed by Shaw et al.